Joe is left home alone by his mum. Fending for himself, he must deal with new friends, threatening foes, and the dodgy parcel of money he's found hidden in his bathroom.
Alone again, Joe loads the cash into his backpack, along with a few clothes, in preparation for running away early the next morning. Late that night, the threatening man (known as the Watcher) turns up demanding his money and tries to kick down Joe's door, but Joe is saved by his neighbour Kosmy. Early the next morning Joe leaves for Paddington Station and is unexpectedly joined by Asha. They don't see that they have been followed by the the Watcher, and this time he's not alone.